阅读说明：本技术 浮动斜盘随动球铰铰接锥形柱塞变量泵/马达旋转组件 (Floating swash plate follow-up spherical hinge hinged conical plunger variable pump/motor rotating assembly ) 是由 胡敏 欧阳震 奚光宇 胡静 曾亿山 刘常海 燕浩 于 2020-06-04 设计创作，主要内容包括：本发明公开了一种浮动斜盘随动球铰铰接锥形柱塞变量泵/马达旋转组件,包括浮动斜盘和锥形柱塞旋转组件。锥形柱塞前端球头与旋转盘球窝铰接,后端只有球面区域与缸体的柱塞孔壁相接触,减小了柱塞副的摩擦面积,得以通过锥形柱塞二力杆受力原理,解决由于传统的固定斜盘式轴向柱塞泵中柱塞所受到的巨大侧向力与力矩导致的摩擦磨损剧烈问题。浮动斜盘的内盘与旋转盘进行固定配合,旋转盘受锥形柱塞球头铰接作用驱动下进行旋转,由于底面滚子与侧面滚珠的支撑作用,旋转盘与内盘一起发生回转运动,从而将原滑靴副中滑靴与斜盘面间的滑移运动转化为侧面滚珠与底面滚子间的滚动运动,因而实现了降低重载滑靴副摩擦功率损失的目的。(The invention discloses a variable pump/motor rotating assembly of a conical plunger piston hinged by a floating swash plate servo spherical hinge. The ball head at the front end of the conical plunger is hinged to the ball socket of the rotating disc, and only the spherical area at the rear end is contacted with the plunger hole wall of the cylinder body, so that the friction area of the plunger pair is reduced, the problem of severe friction and abrasion caused by huge lateral force and moment received by the plunger in the traditional fixed swash plate type axial plunger pump is solved through the conical plunger two-force rod stress principle. The inner disc of the floating swash plate is fixedly matched with the rotating disc, the rotating disc is driven to rotate under the hinging action of the conical plunger ball head, and the rotating disc and the inner disc rotate together under the supporting action of the bottom surface roller and the side surface ball, so that the sliding motion between the sliding shoe and the swash plate surface in the original sliding shoe pair is converted into the rolling motion between the side surface ball and the bottom surface roller, and the purpose of reducing the friction power loss of the heavy-load sliding shoe pair is realized.)

1. A variable displacement pump/motor rotary component of a floating swash plate follow-up spherical hinge articulated tapered plunger, which is characterized in that: including the transmission shaft and install unsteady sloping cam plate subassembly and the toper plunger rotating assembly on the transmission shaft, fixed connection between unsteady sloping cam plate subassembly and the toper plunger rotating assembly, the transmission shaft drive toper plunger rotating assembly and rotate, toper plunger rotating assembly drives unsteady sloping cam plate subassembly and rotates.

2. A floating swashplate follower ball-hinge articulating conical plunger variable displacement pump/motor rotor assembly as claimed in claim 1, wherein: the floating swash plate component comprises an inner plate, a side cover, a floating swash plate chassis and a special-shaped bearing structure of the floating swash plate, the special-shaped bearing structure of the floating swash plate comprises a bottom cylindrical roller thrust bearing consisting of a bottom roller and a bottom retainer and a side angular contact ball bearing consisting of a side ball and a side retainer, the side surface of the inner disc is provided with a roller path for rolling the side surface angular contact ball bearing, the bottom surface of the inner disc is provided with a roller path for rolling the bottom surface cylindrical roller thrust bearing, the inner side surface of the side cover is provided with a roller path for the side surface angular contact ball bearing to roll and support the side surface angular contact ball bearing, the end surface of the floating swash plate chassis is provided with a raceway for rolling a bottom cylindrical roller thrust bearing, the bottom cylindrical roller thrust bearing is arranged between the inner disc bottom raceway and the floating swash plate chassis end surface raceway, and the side surface angular contact ball bearing is arranged between the side surface raceway on the inner side surface of the side cover and the side surface raceway on the inner disc.

3. A floating swashplate follower ball-hinge articulating conical plunger variable displacement pump/motor rotor assembly as claimed in claim 2, wherein: the inner disc is supported and positioned by a side surface angular contact ball bearing and a bottom surface cylindrical roller thrust bearing, is in clearance fit with the floating swash plate chassis and is hermetically installed, and a transmission shaft installation hole is formed in the middle; the side cover is matched with the floating swash plate chassis in an interference fit mode.

4. A floating swashplate follower ball-hinge articulating conical plunger variable displacement pump/motor rotor assembly as claimed in claim 2, wherein: the conical plunger rotating assembly comprises a rotating disc, a return disc, a plurality of conical plungers and a cylinder body, wherein a plurality of ball sockets are uniformly distributed on the rotating disc along the circumference, the front end ball head of each conical plunger is positioned in each ball socket, the ball head is hinged with each ball socket through a spherical hinge, a plurality of through holes corresponding to the ball sockets are formed in the return disc, the through holes in the return disc are aligned with the ball sockets on the rotating disc, the return disc is fixed on the rotating disc, the return disc presses the conical plunger ball head to enable the conical plunger ball head to be matched with the ball sockets, a plurality of plunger holes matched with the conical plungers are formed in the cylinder body, the conical plungers are respectively positioned in the plunger holes, a spherical surface area is arranged at the tail part of each conical plunger, a reciprocating plunger pair friction pair is formed between the spherical surface area and the plunger hole wall of the cylinder body, the front end ball head of each conical plunger is provided with an annular plunger, and metal sealing rings are respectively arranged at two sides, and the middle parts of the rotating disc, the return disc and the cylinder body are respectively provided with a transmission shaft mounting hole.

5. A floating swashplate follower ball-hinge articulating conical plunger variable displacement pump/motor rotor assembly as claimed in claim 4, wherein: the inner disc is matched with the rotating disc in a cylindrical pin and interference fit mode.

6. A floating swashplate follower ball-hinge articulating conical plunger variable displacement pump/motor rotor assembly as claimed in claim 3, wherein: the bottom of the floating swash plate chassis is provided with an oil guide hole channel, the lower end part of the oil guide hole channel is provided with an oil guide groove, the process hole is sealed by a plug, and pressure oil is introduced into a static pressure oil chamber of a sealing space formed by the matching of the floating swash plate chassis and the inner disc through the oil guide groove and the oil guide hole channel, so that static pressure support is realized.

7. A floating swashplate follower ball-hinge articulating conical plunger variable displacement pump/motor rotor assembly as claimed in claim 4, wherein: spring holes are uniformly formed in the cylinder body along the axial circumference, and compression springs are arranged between the bottoms of the spring holes and the spherical hinges.

8. A floating swashplate follower ball-hinge articulating conical plunger variable displacement pump/motor rotor assembly as claimed in claim 4, wherein: the transmission shaft is fixedly connected with a valve plate at the lower end of the cylinder body, and the valve plate is respectively provided with a plurality of waist-shaped oil absorption windows communicated with the plunger holes.

Technical Field

The invention relates to the technical field of fluid transmission and control, is suitable for a swash plate type axial plunger pump/motor, and particularly relates to a variable displacement pump/motor rotating assembly with a floating swash plate and a conical plunger hinged by a spherical hinge.

Background

The swash plate type axial plunger pump/motor is high pressure resistant due to the structural characteristics, can realize various variable functions, particularly can conveniently realize control and adjustment of the displacement of the pump/motor, enables the output power of the pump/motor to be matched with the load, and therefore becomes a wang brand element in the hydraulic transmission technology, is widely applied as the most important core power/execution element in a hydraulic transmission system, is a direct embodiment for measuring the manufacturing and development level and the technological strength of a national hydraulic element, and in the swash plate type axial plunger pump/motor technology, the problems of frictional wear and lubrication failure of a heavy-load friction pair in the swash plate type axial plunger pump/motor are main technical problems for restricting the performance improvement of the swash plate type axial plunger pump/motor.

When the swash plate type plunger pump/motor works, the plunger slides axially in the cylinder body hole to complete the actions of absorbing and pressing oil. The plunger pair is a core friction pair for realizing the oil sucking and discharging functions of the axial plunger pump/motor, the friction lubrication performance of the plunger pair is mainly embodied in the friction force generated by the reciprocating motion of the axial direction of the plunger, and the bearing performance of the plunger pair is mainly embodied in the huge lateral force action needing to be supported in the radial direction of the plunger. The plunger is subjected to key acting forces such as piston shoe reaction force, bush friction force, oil pressure and the like, and the plunger has a variable bias torque due to the fact that the piston shoe reaction force and the axis of the plunger have a variable deflection angle, and abrasion of a friction pair is accelerated. The slipper pair is a friction pair formed by relative sliding motion between the slipper and a swash plate surface, and due to the high speed and load alternating characteristics of the axial plunger pump/motor, the research on the friction lubrication mechanism of the heavy-duty plunger pair and the slipper pair and the design of the friction pair are always difficult points in the research field of the plunger pump/motor.

The friction force of the plunger pair and the sliding shoe pair is an important component of the mechanical loss of the swash plate type axial plunger pump/motor, the leakage amount of the friction force is a key for determining the volumetric efficiency characteristic of the swash plate type axial plunger pump/motor, and the wear failure of the friction force is an important factor for determining the service life and the reliability of the swash plate type axial plunger pump/motor. The technical means for improving the antifriction and antiwear performance of the swash plate type axial plunger pump/motor plunger pair and the sliding shoe pair is based on the lubrication support structure optimization design, the friction interface surface modification and the surface micro-modification technology, some important technical progress is achieved, but the problems are not thoroughly solved, the problems of friction wear and lubrication failure of the plunger pair and the sliding shoe pair are still the most main technical problems restricting the performance of the swash plate type axial plunger pump/motor, and the efficiency of the swash plate type axial plunger pump/motor is low under the working condition of small displacement due to large friction power loss at the plunger pair and the sliding shoe pair, and the overall transmission efficiency of a pump control transmission system is adversely affected.

Disclosure of Invention

The invention aims to make up the defects of the prior art, provides a variable displacement pump/motor rotating assembly of a tapered plunger hinged by a floating swash plate follow-up ball hinge, breaks through the conventional structure, reduces the friction and wear of a slipper pair and a plunger pair under the heavy load of a swash plate type axial plunger pump/motor in the whole working condition range from the fundamental structure principle, improves the reliability and service life of the slipper pair and the plunger pair, and improves the efficiency and performance of the pump.

The invention is realized by the following technical scheme:

a through-shaft type floating swash plate follow-up spherical hinge hinged tapered plunger variable pump/motor rotating assembly comprises a floating swash plate assembly and a tapered plunger rotating assembly:

the floating swash plate assembly is characterized in that a special-shaped bearing structure formed by mutually matching a bottom cylindrical roller thrust bearing and a side angular contact ball bearing is used as a design basis, a static pressure supporting structure is designed in a sealed space formed by matching a floating swash plate chassis and an inner disc, and a mixed support is formed by the special-shaped bearing structure and the special-shaped bearing structure. The special-shaped bearing structure of the floating swash plate is formed by mutually matching a bottom cylindrical roller thrust bearing consisting of a bottom roller and a bottom retainer and a side angular contact ball bearing consisting of a side ball and a side retainer, the bottom cylindrical roller thrust bearing is arranged between an inner plate raceway and a floating swash plate chassis raceway, the side angular contact ball bearing is arranged between a side cover raceway and an inner plate side raceway, the inner plate is matched with a rotating plate in a cylindrical pin and interference fit mode, the inner plate side is provided with the raceway for the side angular contact ball bearing to roll, the bottom surface is provided with the raceway for the bottom cylindrical roller thrust bearing to roll, the inner plate is supported and positioned by the side angular contact ball bearing and the bottom cylindrical roller thrust bearing and is in clearance fit with and sealed installation with the floating swash plate chassis, meanwhile, the installation position of a transmission shaft is reserved, and the side cover is matched with the floating swash plate chassis in an interference fit mode, the side surface is provided with a roller path for rolling the side surface angular contact ball bearing and supporting the side surface angular contact ball bearing, the end surface of the floating swash plate chassis is provided with the roller path for rolling the bottom surface cylindrical roller thrust bearing and an oil guide hole channel, a process hole processed by plug sealing is used, pressure oil is introduced into an inner oil channel in the floating swash plate chassis through the oil guide groove and the oil guide hole channel and is guided into a sealed space oil chamber formed by matching the floating swash plate chassis and the inner disc, and thus static pressure support is realized;

the conical plunger rotating assembly comprises a rotating disk, a return disk, a conical plunger, a spherical hinge, a spring and a cylinder body, wherein the return disk is matched with the rotating disk through a screw and presses a conical plunger ball head to enable the conical plunger ball head to be hinged with rotating disk ball sockets distributed on the rotating disk, an annular oil groove is formed in the ball head of the conical plunger, two ends of the spherical surface of the tail portion of the conical plunger are respectively provided with a groove and are respectively provided with a metal sealing ring to seal oil in a plunger cavity, and the spherical surface of the tail portion of the conical plunger and a plunger hole wall of the cylinder body form a reciprocating plunger pair friction. The ball head at the front end of the conical plunger is hinged with the ball socket of the rotating disc, and only the spherical surface at the rear end is contacted with the plunger hole wall of the cylinder body, so that the friction contact area of the plunger pair is reduced, and the conical plunger forms a two-force-rod stress working condition, so that the acting force between the plunger and the plunger hole wall is greatly reduced, and the friction force and the friction power loss at the plunger pair can be remarkably reduced;

the connection mode between the inner disc and the rotating disc adopts a cylindrical pin and interference fit connection mode, and other connection modes (such as screws, pins and the like) can also be adopted;

an oil chamber for supporting and storing high-pressure oil by static pressure is formed between the inner disc and the floating swash plate chassis, and the high-pressure oil in the oil chamber is sealed in a clearance sealing mode;

the side cover is matched with the floating swash plate chassis in an interference fit mode and can also be connected with the floating swash plate chassis through screws;

the rolling bodies of the side surface angular contact ball bearing and the bottom surface cylindrical roller thrust bearing can be 3 or more than 3;

the conical plunger and the plunger holes in the cylinder body are uniformly distributed along the axial circumference of the cylinder body, ball sockets distributed on the rotating disc are hinged with a conical plunger ball head, a pump transmission shaft is driven by a prime mover, the conical plunger in the cylinder body and the cylinder hole is driven to rotate through spline connection, and the rotating disc is driven by the conical plunger ball head to rotate together;

spring holes are uniformly formed in the axial circumference of the cylinder body, compression springs are arranged between the bottoms of the spring holes of the cylinder body and the spherical hinges, and the rotary disc and the whole rotary assembly fixed with the rotary disc are pre-compressed before the pressure of the pump is not formed.

The invention has the advantages that:

the inner disc of the floating swash plate assembly is matched with the rotating disc in a cylindrical pin and interference fit mode, the rotating disc is driven to rotate under the hinging action of the conical plunger ball head, the rotating disc and the inner disc rotate together under the supporting action of the bottom surface roller and the side surface ball, so that the sliding motion between the slipper shoes and the swash plate surface in the original slipper shoe pair is converted into the rolling motion between the side surface ball and the bottom surface roller, the aim of reducing the friction power loss of the heavy-load slipper shoe pair is fulfilled, the floating swash plate is wholly immersed in hydraulic oil during working, the lubricating and cooling are sufficient, and the mixed support bearing mode of the combined action of the bearing support and the static pressure support is adopted, the floating swash plate can achieve longer service life through reasonable design, and the floating swash plate is convenient to maintain and replace when being worn;

the ball head at the front end of the conical plunger is hinged to the ball socket of the rotating disc, only the spherical surface of the rear end of the conical plunger contacts with the plunger hole wall of the cylinder body in a tangent mode to form a plunger pair, the friction contact area of the plunger pair is greatly reduced, and the conical plunger is made to form a two-force rod stress working condition, so that the acting force between the plunger and the plunger hole wall is greatly reduced, the friction force and the friction power loss at the plunger pair can be remarkably reduced, and the problem of severe friction and abrasion of the plunger pair caused by the huge lateral force and the moment of the plunger in the traditional fixed swash plate type axial plunger pump/motor is solved. The metal sealing rings arranged at the grooves on the two sides of the spherical surface of the conical plunger can reduce the flow leakage at the plunger pair. Spring holes are uniformly formed in the axial circumference of the cylinder body, compression springs are arranged between the bottoms of the spring holes of the cylinder body and the spherical hinges, and the rotary disc and the whole rotary assembly fixed with the rotary disc are pre-compressed before the pressure of the pump is not formed. Therefore, the friction wear of the slipper pair and the plunger pair under the heavy load of the swash plate type axial plunger pump/motor can be reduced in the full working condition range, the reliability and the service life of the slipper pair and the plunger pair are improved, and the efficiency performance of the pump is improved.

Drawings

FIG. 1 is a schematic view of the internal parts of a pump body fitted with the assembly of the present invention;

FIG. 2 is an enlarged view of a portion of the cylinder spring bore;

FIG. 3 is a diagram of a pump body with the assembly of the present invention installed;

FIG. 4 is a partial part sectional view of the conical plunger rotary assembly;

FIG. 5 is a schematic view of a bottom surface cylindrical roller thrust bearing and a side angular contact ball bearing configuration;

FIG. 6 is a left side elevational view of the swash plate assembly;

FIG. 7 is a cross-sectional view A-A of the swash plate assembly;

FIG. 8 is a rear view of the swash plate assembly;

FIG. 9 is a cross-sectional view B-B of the swash plate assembly;

FIG. 10 is a three-dimensional view of the overall appearance of the swash plate assembly;

FIG. 11 is a schematic view of the manner in which the rotating plate and the swash plate are connected by the cylindrical pins.

Detailed Description

As shown in fig. 1, a through-shaft floating swash plate follow-up ball hinge conical plunger variable displacement pump/motor rotating assembly comprises a floating swash plate assembly and a conical plunger rotating assembly:

as shown in fig. 5-10, the swash plate assembly is based on a special-shaped bearing structure formed by a bottom cylindrical roller thrust bearing and a side angular contact ball bearing, and realizes a static pressure support structure in a sealed space formed by the matching of the swash plate chassis 3 and the inner disc 15, and forms a hybrid support together with the special-shaped bearing structure, and is characterized in that: the swash plate type axial plunger pump/motor comprises an inner disc 15, side balls 9, a side retainer 10, bottom rollers 11, a bottom retainer 12, a side cover 16 and a floating swash plate chassis 3, is applied to a swash plate type axial plunger pump/motor, and can be used for replacing an original swash plate. The special-shaped bearing structure of the floating swash plate comprises a bottom cylindrical roller thrust bearing consisting of a bottom roller 11 and a bottom retainer 12 and a side angular contact ball bearing consisting of a side ball 9 and a side retainer 10, wherein the bottom cylindrical roller thrust bearing is arranged between a roller path of an inner plate 15 and a roller path of a chassis 3 of the floating swash plate, the side angular contact ball bearing is arranged between a roller path of a side cover 16 and a side roller path of the inner plate 15, the inner plate 15 is matched with a rotating disc 14 in an interference fit mode by adopting a cylindrical pin 17, the side surface of the inner plate 15 is provided with a roller path for the side angular contact ball bearing to roll, the bottom surface is provided with a roller path for the bottom cylindrical roller thrust bearing to roll, the inner plate 15 is supported and positioned by the side angular contact ball bearing and the bottom cylindrical roller thrust bearing and is in clearance fit with the chassis 3 of the floating swash plate and is installed, the side cover 16 is matched with the floating swash plate chassis 3 in an interference fit mode, a raceway for rolling the side surface angular contact ball bearing and supporting the side surface angular contact ball bearing is arranged on the side surface, the raceway for rolling the bottom surface cylindrical roller thrust bearing is arranged on the end surface of the floating swash plate chassis 3, an oil guide hole channel 19 is arranged on the end surface of the floating swash plate chassis 3, a process hole is sealed and processed by a plug 18, pressure oil is introduced into an inner flow channel in the floating swash plate chassis 3 through an oil guide groove 20 and the oil guide hole channel 19 and is guided into a static pressure oil chamber 21 of a sealed space formed by matching the floating swash plate chassis 3 and the inner disc 15, and static pressure support is realized;

as shown in fig. 2, 3 and 4, the conical plunger rotating assembly comprises a rotating disk 14, a return disk 13, a conical plunger 6, a ball joint 8, a spring 24 and a cylinder 4, wherein the return disk 13 is matched with the rotating disk 14 by a screw 22 and presses a ball head of the conical plunger 6 to be matched with the rotating disk ball joints 23 distributed on the rotating disk 14, a plurality of ball joints 23 are uniformly distributed on the rotating disk 14 along the circumference, the ball head at the front end of the conical plunger 6 is positioned in the ball joints 23, the ball head is hinged with the ball joints 23 by the ball joint 8, a plurality of through holes corresponding to the ball joints are formed on the return disk 13, the through holes on the return disk 13 are aligned with the ball joints 23 on the rotating disk 14 and the return disk 13 is fixed on the rotating disk 14, the ball head of the conical plunger 6 is provided with an annular oil groove, the tail of the conical plunger 6 comprises an area, and metal sealing rings 7 are respectively installed on two sides, the spherical surface of the tail part of the conical plunger 6 and the plunger hole wall of the cylinder body 4 form a plunger pair friction pair which moves in a reciprocating manner. The ball head at the front end of the conical plunger 6 is hinged with the ball socket of the rotating disc 14, and only the spherical surface at the rear end is contacted with the plunger hole wall of the cylinder body 4, so that the friction contact area of the plunger pair is reduced, the conical plunger 6 forms a two-force rod stress working condition, and the flow leakage at the plunger pair can be reduced due to the sealing effect of the metal sealing rings 7 arranged at the grooves at the two sides of the spherical surface at the tail part of the conical plunger.

As shown in fig. 11, the connection mode between the inner disc 15 and the rotating disc 14 is a cylindrical pin 17 and interference fit connection mode, and other connection modes (such as screws, pins, etc.) may also be adopted;

an oil chamber for supporting and storing high-pressure oil by static pressure is formed between the inner disc 15 and the floating swash plate chassis 3, and the high-pressure oil in the oil chamber is sealed in a clearance sealing mode;

the side cover 16 is matched with the floating swash plate chassis 3 in an interference fit mode, and can also be connected with the floating swash plate chassis 3 through screws;

the rolling bodies of the side surface angular contact ball bearing and the bottom surface cylindrical roller thrust bearing can be 3 or more than 3;

the inclination angle of the floating swash plate chassis 3 relative to the base 2 can be adjusted, so that the stepless regulation of flow is realized;

two metal sealing rings 7 are arranged at the tail part of the conical plunger 6.

The conical plunger 6 and the plunger holes on the cylinder body 4 are uniformly distributed along the axial circumference of the cylinder body, the ball sockets 23 distributed on the rotating disc are hinged with the ball head of the conical plunger 14, the pump transmission shaft 1 is driven by a prime motor, and the conical plunger 6 in the cylinder body 4 and the cylinder hole is driven to rotate through spline connection;

the ball head at the front end of the conical plunger 6 is hinged with the rotating disc ball socket 23, and only the spherical surface at the rear end is in contact with the plunger hole wall of the cylinder body 4, so that the friction contact area of the plunger pair is reduced, and the conical plunger 6 meets the two-force rod stress condition.

Spring holes are uniformly formed in the axial circumference of the cylinder body 4, a compression spring 24 is arranged between the bottom of the spring hole of the cylinder body and the ball 8, and the function of pre-compressing the rotating disc 14 and the whole rotating assembly fixed with the rotating disc is achieved before the pump pressure is not formed.

A valve plate 5 is fixedly connected to the lower end of the cylinder body 4 on the transmission shaft 1, and a plurality of waist-shaped oil absorption windows communicated with the plunger holes are respectively arranged on the valve plate 5.

The working process of the invention is as follows:

a through-shaft type floating swash plate follow-up spherical hinge hinged tapered plunger variable pump/motor rotating assembly comprises a floating swash plate and a tapered plunger rotating assembly, and is placed in a swash plate type axial plunger pump as an example:

the conical plunger 6 is arranged in a plunger hole of the cylinder body 4 and is pressed towards the rotating disc 14 under the action of the return disc 13, and the return disc 13 is fixedly connected with the rotating disc 14 through a screw 22. The conical plunger 6 and the plunger holes on the cylinder body 4 are uniformly distributed along the axial circumference of the cylinder body 4, and the ball sockets 23 distributed on the rotating disk 14 are hinged with the ball head of the conical plunger 6. The pump transmission shaft 1 is driven by a prime motor, and drives the cylinder body 4 and the conical plunger 6 in the cylinder hole to rotate through spline connection, the conical plunger 6 gradually extends outwards in a half-cycle (0-pi) of top-to-bottom rotation in the cylinder body 4 under the action of the pressing force of the return disc 13, so that the volume of a sealed working cavity of the plunger hole of the cylinder body 4 is continuously increased, local vacuum is generated, and oil is sucked in through the kidney-shaped oil suction window on the valve plate 5 through the valve plate 5; and conversely, when the plunger piston rotates within a half cycle (pi-2 pi) from bottom to top, the plunger piston is gradually retracted into the cylinder under the extrusion force of the inclined rotating disk 6, so that the volume of the sealed working cavity is continuously reduced, namely, the oil is outwards pressed from the kidney-shaped oil discharge window on the port plate 5.

The tail part of the conical plunger 6 comprises a spherical surface area, and the spherical surface of the tail part of the conical plunger 6 and the plunger hole wall of the cylinder body 4 form a plunger pair friction pair which moves in a reciprocating manner. The ball head at the front end of the conical plunger is hinged to the ball socket 23 of the rotating disc, only the spherical surface of the rear end of the conical plunger contacts with the wall of the plunger hole of the cylinder body, the friction contact area of the plunger pair is reduced, the two-force rod stress principle of the conical plunger 6 is utilized, the acting force between the plunger and the wall of the plunger hole is greatly reduced, the friction force and the friction power loss at the plunger pair can be remarkably reduced, and the problem of severe friction and abrasion of the plunger pair caused by huge lateral force and moment of the cylinder plunger in the traditional fixed swash plate type axial plunger pump is solved. Due to the sealing effect of the metal sealing rings 7 arranged at the grooves on the two sides of the spherical surface at the tail part of the conical plunger, the flow leakage at the plunger pair can be reduced. Spring holes are uniformly formed in the axial circumference of the cylinder body 4, a compression spring 24 is arranged between the bottom of the spring hole of the cylinder body and the spherical hinge 8, and the rotary disc and the whole rotary assembly fixed with the rotary disc are pre-compressed before the pump pressure is formed. The rotating disc 14 is driven by the ball joint hinge action of the conical plunger 6 to rotate under the torque action around the central line thereof, the rotating disc 14 is fixedly arranged with the inner disc 15 of the floating swash plate by adopting a cylindrical pin and interference fit mode, and is provided with a special-shaped bearing structure consisting of a side surface angular contact ball bearing and a bottom surface cylindrical roller thrust bearing, and the static pressure thrust generated by the high-pressure oil in the oil chamber, the side angular contact ball bearing is supported by the side cover 16 and the roller path in the inner disc 15, the bottom cylindrical roller thrust bearing is supported by the roller path in the inner disc 15 and the floating swash plate chassis 3 respectively, and the side cover 16 and the floating swash plate chassis 3 are arranged together in an interference fit, so that under the action of the torque around the central line of the rotating disc 14, the floating swash plate inner disc 15 rotates together, and the rotating direction of the rotating swash plate inner disc is consistent with the rotating disc 14. Therefore, the sliding motion between the sliding shoes and the inclined disc surface in the original sliding shoe pair is converted into the rolling motion between the side balls and the bottom surface rollers, so that the purpose of reducing the friction power loss of the heavy-load sliding shoe pair is achieved, the floating swash plate is wholly immersed in hydraulic oil during working, the lubricating and cooling are sufficient, in addition, the bearing form of the combined action of the bearing support and the static pressure support is adopted, the longer service life can be reached through the reasonable design of the floating swash plate, and the floating swash plate is convenient to maintain and replace when being worn.

The invention can reduce the friction and abrasion of the sliding shoe pair and the plunger pair under the heavy load of the swash plate type axial plunger pump in the full working condition range, improve the reliability and service life of the sliding shoe pair and the plunger pair, and improve the efficiency performance of the pump.

The embodiments described in this specification are merely illustrative of implementations of the inventive concept and the scope of the present invention should not be considered limited to the specific forms set forth in the embodiments but encompasses equivalent technical means as would be appreciated by those skilled in the art based on the inventive concept.